Concentration of minerals by flotation.



ILR. LIVINGSTON.

" CONCENTMTION 0F MINERALS BY FLOTATION. v

- umcn'm man 050.2 7. ma.

Patented July 20, 1915.

5 SHEETSSHEET I.

A. R. LEVINGSTON. I CONCENTRATION OF MINERALS BY FLOTATION.

:4 APPLICATION FILED DEC,27, 1913.

-. 1,147,633. PatentedJuly 20,1915.

KSHEETS-SHEET 2 "mun-11A i i/IT/VESSES A. B. LIVINGSTON. coucsmmonor MINERALS BY nomzou. APPLICATION FILED DEC-Z7. 1913. I 1,147,633, Patented July 20, 1915.

s SHEETS-SHEET 3.

; WITNESSES I I Q i A. R. LIVINGSTON. CONCENTRATION OF MINERALS BY FL0TATIQN. AFPLICATION FILED 020.21. 3913. 1,147,633, 1 Patented July 20, 1915.

5 SHEETS-SHEETA.

WITNESSES l/VVE/V 7'09 .'v

A. uymesmu. CONCENTRAHON OI MINERALS BY FLOTATION.

v APPLICATION FILED DEC.27, 1913. 1,147, 33, Patented July 20, 1915.

- 5 SHEETS-SHEET 5- 'IIIIIIIIIIIIIlIIIIllllIIII/Ifl action of the main body of Water, to excep- I UNITED STATES PATENT ARClHIBALD R. LIVINGSTON, OF CANON CITY, l'JOLORADO, ASSIGNOR TO THE NEW JERSEY ZINC COMPANY, 01 5 NEW YORK, N. Y., A CORPORATION OF NEW JERSEY;

CONCENTRATION OF MINERALS BY FLOTATION.

mamas. I

Specification of Letters Patent.

Patented July 20, 1915.

Application filed December 27, 1913. Serial No. 808,945. H

The present invention relates to the separation of fioatable minerals from material with which they are associated.

It contemplates, as a preliminary operation, grinding or crushing the material to be separated, (for instance, zinc blende and other sulfids associated with calcite, silica, roasted pyrites, or the like) to say from 1+ to 16 mesh, and then mixing the mass with the customary emulsion of sulfuric acid, oil and Water, prior to flotation. The effect of the sulfuric acid is apparently to clean the oXid from the surface of the sulfid particles, and the oil thereupon envelops the cleaned particles, thus rendering them more susceptible to flotation. Calcite, silica, and the like, will not receive an oil film and are not subject to flotation therebv.

The present invention is based upon the conception that an effective disentanglement and'flotation of the floatable minerals can be effected, by feeding the mixture into or upon a body of Water, and then bringing it up through the surface of the water to such a height that theemerging top layer will meet a continuous downflow of water, which, as a thinfilm, encounters the rising material, dis-- entangles the top layer ,thereof, thereby bringing it into suspension .;1 the descend- -1ng water film, lowering its angle of repose and causing it to flow down into the main body or" water at so slight an angle to the surface thereof as to enter it quietly. The' top layer of the continuously emerging material, being thus constantly renewed, and progressively brought into suspension, as described, so as to be in condition of disentanglement, is thus presented to the flotation tional advantage. The particles not susceptible to flotation drop below the surface of the water, and, during the further progress of the operation, are fedlongitudinally bulk of the separation incident to the practice of the invention is, however, efiected during the primary stages thereof, that is to say, in the near vicinity of the feed of the material into the flotation apparatus, as will hereinafter more fully appear.

In order to insure that the body of the material undergoing separation shalhrise through the surface of the Water continuously and uniformly, I provide the flotation zqiparatus With-suitable means for preventing any backward slide or slump of the material as a Whole, which u ould otherwise occur unless provision is taken to guard against it. In practice, these means may conveniently consist of suitable projections distributed with uniformity over the interior periphery of the flotation apparatus, 'and of such a character as to prevent the back slide referred to, while not interfering with the disentanglement of the continu ously emerging top layer by the down.- flowing Water. film.

A conspicuous advantage of the present invention residesin the fact that the downflowing film of Water which meets the rising top layer of the material to be separated is supplied by water spra s and carries with it a notable quantity 0 air, which adheres to the oil-coated sulfids and facilitates their flotation. To further enhance this favorable effect, I prefer to take special means for increasing the quantity of. air carried by the water film, as, for instance, by causing the pipes which supply water to the spray to automatically draw in air from. the surrounding atmosphere. T

In order that theaoperation shall be effective, the sulfids to be separated should be in the same condition as freshly mined sulfids, that is to say, substantially unaltered'by sur-' face oxidation, or should be restored to that 105 condition by some appropriate treatment. The level of the water in the drum, in those instances where the drum is cylindrical and horizontal should preferably be established at a plane not higher than 45. above-the lowest point of the drum, and the t iio of the water being conducive to its capac-.

ity for retaining air in suspension therein.

The drum may he of equal diameter throughout, orv it may taper, so as to he ol larger diameter at one end than at the other: or it may be duplex, in the sense o'l having a transverse partition midway of its ends, so that the material to he separated can he fed into the water near the middle partition,

. on opposite sides thereof. So also, the drum may he placed either horizontally or at a slight incline.

'lhe concentrates may he discharged either at the same end of the drum as the taihngs, or at. the opposite end. Thus, hy providing a horizontal drum, at one of its ends, with an annular weir or dam, the. concentrates may he tloated over said dam at one end ol the drum andthe tailings discharged at the other end. 01-, by making the dam sulliciently high, and providing an additional dam in the tailings receptacle, the concentratcs can he taken otl' at the same end of the drum as the tailings. ()r, it the-drum is inclined, concentrates can be taken olT-at one end, and tailings at the opposite end, with-' out. providing a dam; in which case, the level 01'' the water will merely reach to the lower edge of the upper open end o'l"the drum, said upper open end constituting, in suhstance, asubstitute for the annular weir ol' t'he dam. The concentrates can he sepa rated 01" graded, during the operation, if desired, by means of a stationary trough or troughs entering the interior of the drum, as will hereinafter more fully appear.

In order to hasten the progress of the ore through the drum, there may he provided a series of uprightadjustahle hlades, located in proximity to the lower inner wall oi the drum, and having atorward slant or incline,

so that when the ore is returned into the water, theseslanting hlades cause it to move correspondingly and progressively toward. the tailings end ot the drum. 'l'hes:- slant.- ing hlades may he located, for instance, immediately below the. trough or troughs, when the troughs are employed, and may he secured thereto.

As for the trough or troughs then'iselves, it will he understood that their side or sides rise to the level of the water, so that the floated minerals fall over the top edges of the trough when the apparatus is in service.

In. order thatithis Falling over of the. particles over the top edges ol the troughs may take place smoothly. it is desirahle to provide the top edges with a sheet o'l' lead holted or otherwise secured. thereto in an upright position and capahle otheing planed oli evenly to the level ol' the water, therehy making a clean smooth surlace over which the. floated particles can pass without hindrance.

As hereinhel'ore noted, the drum need not rotate continumisly in one (.lirection. hut. may oscillate, in which latter event, the water spray lilin will he applied to both sides of the oscillatory drum. ()r, the drum may remain stationary and he provided with a lining, say ol' ruhber, which may he oscillated inside of the stationary drum, so as to alternately raise the hody ol' ()l'lillHH't} the surface of the water. When the, drum is oscillated, or when the oscillating lining is employed. it is likewise desirahlc to provide projections therefrom, as hereinlwl'ore retcrrcd to for the; purpose of carrying the emerging top layer to a higher level than its natural angle ol repose, and for the pur mse ot preventing a backward slump ol the ore as a whole.

Referring to the drawing -Figure l. represents a cross-sectional view, partly in eles vation, ot a drum and-its adjuncts, suitahle l'or the practice of the invention; Fig. 2 represents a fra mentary view thereol', on a larger scale; I ig. 5 represents a longitudinal sectional view,'on a somewhat smaller scale, ot the apparatus shown in Figs. 1 and 2; Figk l represents a like view ot a lll ltllfi(J2l-.

tion, illustrating the employment. of a plu rality ot' separat mg troughs nested one withiuthe other: Fig. 5 represents, on a larger scale, a sectional view taken on the line 5 1) of Fig. l; Fig. 1 represents a l ragnu-in tary view thcreol; Fig. 7 represents a view similar to Fi 33 and l ol a l'urther modilication of the invention. characterized hy the enmlovment ol a series oltroughs ranged side by side: Fig. H'represeuts a cross-sectional view, taken on a somewhat larger scale. on the line 8- o'l Fig. 7; Fig. i) represents a top plan view of the troughs ol the laterally arranged type shown in Figs. 7 and 8;

Figs. ll), l1, l2 and 13, represent various modifications, in longitudinal section, the main elements of the apparatus being shown, without. illustrating the more specilic details of construction. Fig. It represents a vertical longitudinal section ol' a further modilication and Fig. .15 represents a cross-sectional elevation thereof on the line 15-l5 ol Fig. l-l. Fig. 16 represents a still further modification, in perspective.

Referring to the drawings, A indicates an opelrended drum or barrel, which may he made of wood, and which is'provided with metal hands a resting upon flanged iele b .rso

19 in the form of the invention shown in Fig.

3, the drum A is shown as horizontal, and is provided at the feed end with an annular Weir or dam g,'as shown, for the purpose of maintaining a suitable water level in the drum. The tailin s are received in a receptacle C, and the longitudinally inclined bottom, as shown.

The supply of ore tobe separated enters through the feed chute D, and may discharge in any suitable manner into the water contained within the drum, as, for instance, in proximity to the interior periphery thereof, near one end of the drum, as shown in Figs. 1, 2, 3, 7 and 8;.or it maydischarge upon or into the water in some other Way,as, for

instance, at or near the central vertical axial plane thereof, as'indicated in Figs. 10 to 13, inclusive. I

A perforated raypipe h is provided, extending longitu inally through the drum, which spray pipe may be provided with nozzles 11., as indicated in Figs. 1, 2 and 3,

or with merely a row of perforations 72. as shown iii-Figs. 4 and 5.- The spray get nozzles h, or the perforations h as the case may be, are in proximity to the rising till 1 and 2), and the ore,

side of the drum, and are so directed that the Water therefrom will-strike the inner wall of the-rising side of the drum at or about the central horizontal axial plane thereof and willfiow down in a practically unbroken sheet to meet the top layer of the emerging body or ore as it is carried up by the projections hereinbefore referred to. As indicated, the inner Wall of the drum is provided with the said projections, which may conveniently take the form of beaded. tacks or brads, or the like, spaced about half an inch apart, and with some fair degree of uniform'ityjof distribution.

1n the practice of the invention, in the form of apparatus shown in Figs. 1, 2 and 3, the tailings receptacle is filled with water and the level is raised therein until it enters the drum and begins to flow over the end weir or dam g and likewise over the side of the trough E adjacent to the rising side of the drum. The drum is then rotated, for

instance, in the direction of the arrow (Figs. which has first been stirred in a suitable agitating tank with the standard emulsion of oil, sulfuric acid and water, is \fed continuously through the feed ibex' or chute intoflthe water conoated sulfids or.concentrades are received in a trough E, having a tained in the 'drum.- As the drum rotates, the top layer of the ore thus fed into it is brought up.as it emerges from the water to such a height that it meets a continuous downfiow of water, which, use thin film, encounters the rising material, disentangles the top layer from the rising side of the drum and the headed tacks or brads, and brings it into suspension in the descending water film. Accordingly, the angle of repose of the top portion of the emerging ore is lowered and it is caused to. flow down into the main body of water at so slight an angle to the surface thereof as to enter it quietly. At the same time, the headed tacks or brads, or the like, prevent the back slide of the main body of ore, and even retain it at an angle higher than its normalangle of repose, thereby contribhting to the relatively gentle manner in which the particles of the top layer which have been brought into suspension in the downfiowing water lilm enter the main body of water within the drum.

The top portion of the continuously emerging material, being thus constantly renewed, is progressively brought into suspension and flows into the main body of water within the drum, in a gentle manner, and at the surface thereof, in a condition of considerable disentanglement, and by means of a film of water relatively cold and highly aerated, is presented under particularly favorable conditions to the flotation action of the main body of Water. Accordingly, the great bulk of the flotable particles is separated during the early stages of the operatiom'that is to say, in the vicinity ofthe feed end of the drum. The particles not susceptible to floof the water,

tation drop below the surface and, during the further progress of the operation, are fed longitudinally'of the apparatus employed, and, being'themselves repeatedly brought up through "the body of water to meet the descending water film, are gradually relieved of such of the floatable particles as they may chance to carry with them.

As hereinbefore-indicated, the temperature of the water, if low, favors the separation because of its greater capacity, when cold-,to occlude air, so that the water sprays are more efficient as a means for aerating the 'water film which they form, under such cir cumstances. To increase the aeration of the water, any suitable air injecting device may be employed; as, for instance, the ogee-pipe section 1 0 which, inserted in the supply pipe, will draw in air through the open nipple h thereby supplying the sprays or perforations with water containing a considerable increment of air. The

izs

slanting blades o, hereinbefore referred t attached tothe ings compartment.

In the form of the invention shownin Figs. 4'and 5, the drum is shown ot a larger diameter at one end than at the other, although its e'en-iral axial plane is horizontal. Instead ot'a sin le tronh E, it contains M A b 1'. three troughs la .lu- 1a", nested one witnin the other, so as to take oil different grades .ofconcentrates; the middlings may, it desired, be returned, for retreatn'ient, which may be desirable, in some instances. It will, of course, be understood that the number of troughs employed may be varied, to suit particular conditions of use. As shown in Figs. 1 and 2, but one side only of the trough may be used for receiving the floated concentrates, that is to say, the side of the trough adjacent to the rising side of the drum, and this will be preferable in those instances where a greater ilow of water over the edge of the trough is desired. Usually, the floated concentrates on the other side of the trough are inconsiderable in amount, but when it is desired to recover them also, the floated concentrates may he received over both sides of the trough, as indicated in Fig. 5, but, in such instance, the depth of the flow of water .over the top edges of the trough, other conditions being equal. will be less, as will be readily understood.

In Figs. 1 and 2, I have indicated means which I. prefer to employ in order to make the top edges of the trough smooth, and to keep them so. These means consist of an upright plate of lead '10 attached to the wooden side of the trough by threaded bolts iassin throu h slots in the dates. The n 3- 1 b h per edge of this lead plate may be planed oil smooth, and, if nicked or otherwise worn during the service of the apparatus, may be replaned and readjusted in height, thereby providing a permanently smooth upper edge for the troughs.

In the form of the invention shown in Figs. 7, 8 and 9, I have retained the same general features of construction shown in Figs. 1, 2 and 3, but I have substituted for the trough E, three troughs E, E I5, arranged side by side, and of different depths and lengths, as indicated. These troughs are adapted to take off different grades of concentrates, as are the nested troughs of the apparatus shown in Figs. 4 and 5, and

constitute a modification adapted for that purpose. In Fig. 8, I have also shown the feature ofa rubber lining :12 provided with rubber projections integral therewith and spaced uniformly apart at distances of about half an inch, these projections subserving the same general purposes as the headed tacks, but being capable of more ready application to the drum and more ready of replacement, inv case of wear. This feature is more fully shown in Figs. 4: and 5.

Figs. 10 to 13 of the drawings illustrate.

various arrangements of the drum with relation to the tailings and concentrates receptacles. lhus, in t' form of the invention shown in Fig. l( e arrangement and const-ruction of the parts is substantially the same as in the form shown in Figs. 7, 8 and t), except that the drum A of Fig. 10, is provided with a central transversepartition 72, thereby making it duplex, and the feed to the drum discharges'in close proximity to this partition, on opposite sides thereof. Soalso, the tailings tanks C are dupli :ated, as are also the sets of concen trates troughs.

In the term of the invention shown in Fig. 11, the troughs are omitted, the drum A discharges into the tailings tank C and the (JUIICBDtlfltQS are received in the concentrates trough E In the form. of the invention shown in Fig. 12, the cylindrical drum A" is arranged at an incline, thesame relative arrangement; of parts being observed as in Fig. 11. In theform of the invention shown in Fig. 13, the drum A likewise shown as inclined, but is devoid of the annular weir at the feed end thereof, the edge of the upper end of the inclined drum, serving as the weir or dam for the concentrates discharge. In Fig. 12, C", in.- dicates the tai'lings .l'QCQl')tilCl6 and Ff, the concentrates reccptacle. In Fig. 13, C indicates the tailings receptacle and E the concentrates receptacle.

It will, of course, be understood, that, inasmuch as Figs. 10 to 13, are intended merely to illustrate the relative modifications of the arrangement of the rotatory or oscillatory drum with respect to the tailings receptacles and concentrates receptacles, the illustration of the other features thereof, as,

for supporting it-up'on the'idler rolls b, as shown. In order to oscillate the drum, a band a of any suitable flexible materialmay be attached to the drums periphery and to the periphery of two independently mounted sheaves or band-wheels F, which are fixed upon rock-shafts 3. These rock-shafts may be connected to actuating arms 25, connected to a pitman G, adaptedto be reciprocated in any suitable manner, as, for instance, by the power driven pulzey H and its crank I. The features of construction of the drum and its accessories are the same as in Figs. 1, 2 and 3, except that the waterspray is duplicated. as shown particularly in Fig. 15, so that the water-spray film may be applied to both sides of the oscillatory drum.

In tne form of the invention shown in To this end, the drum may be provided with hands a.

, substantially as described.

Fig. 16, the drum is made stafiienary, for which, purpose it may 'rest upon'and be attached to suitable cradle supports J It is provided with a lining a" of rubber, pro

.vided with projections as shown. and this lining is oscillated in any suitable manner, as, for instance, b attaching its ends to ,the rocking cylin ers K, adapted to be rocked by the arms I?" connected to the pitman G, which latter is reciprocated by a' crank I, or Otherwise. In this modification, also, the spray-pipe is duplicated.

at I claim is:

l. The method of separating floatable minerals from material with which they are associated, which consists in feeding the mixture into a body of Water, progressively raising it through the surface of the water, meeting the emerging top layer by a downflowing filmo'f water, and floating the top layer thereby into the main body of water at the surface thereof and collecting the ma-, terial thereby separated separately from that which sinks; substantially as described.

2. The method .of separating fioatable minerals from material with which they are associated, which consists in feeding the mixture into a body of water, progressively raising it through the surface of the water at an angle greater than its natural angle of repose, lowering the angle of repose of the emerging top layer .by a-downflowing film of water and floating the top layer into the. main body of the water at the surface thereof and collectin the material thereby separated separately rom that which sinks;

3. The method of separating floatable minerals from material with which they are associated, which consists in feeding the mixture into a body of water, progressively sta-ntially as described.

raising it through the surface of the water,

meeting the emerging top layer by a downflowing film of aerated waterand floating thereby the top layerinto the main body of water at the surface thereof; substantially as described.

4. The method of separating floatable minerals from material with which'they are associated, ,which consists in feeding .the mixture into abody of water, progressively raising it through the surface of the Water,

meeting the emerging top layer by a downflowing film of water produced by spray jetsv and floating thereby the top layer into the main body of water at the surface thereof and collecting the material thereby separated separately from that which sinks; sub- The method of separating 'floatable minerals from material with which they are associated, which consists in feeding the mixture into a body of water, progressively raising it through the surface of the water,

meeting the emerging top layer by a down? jets of aerated water, and floating thereby the top layer into the main body of water 'at the surface thereof; substantially as described. I

6. 'The,.; method of separating floatable minerals from material with which they are associated. which consists in feeding the mixture into the body of water, progressively raising it through the surface of the water at an angle greater than its natural angle of repose, meeting the emerging top layer by a' downflowing film of water and thereby lowering the angle of repose of the top layer, saidv downflowing film of water being impregnated with air, and floating the top layer into the main body of water at the surface thereof; substantially as described.

7. Apparatus for the separation of floatable minerals from material with which they are associated, said apparatus comprising a. rotatory drum, means for maintaining a body of flotation liquid therein, means for feeding the material to be separated into the flotation liquid, means for supplying a downflow film of water to the inner periphery of the drum on the rising side thereof, and means for collecting material floated upon the body of flotation liquid separately from that which sinks; substantially as described.

flowing film of water produced by spray 8. Apparatus for the separation of floatable minerals from material with which they are associated, said apparatus comprising a rotatory drum, means for maintaining a body or flotation liquid therein, means for feeding the material to be separated into the flotation liquid, a. spray pipe for supplying wash water to the inner periphery of the drum-above the water leyel; thereof and means for collecting material floated upon the body of flotation liquid separately from that which sinks; substantially as described. V

9. Apparatus for the separation of floatable minerals from material with with they are associated, said apparatus comprising a rotatory drum, means for maintaining a bodv of flotation liquid therein, means for feeding the material to be separated into the flotation liquid, a spray pipe for supplying of, and a eolleetor comprising a trough- ,strueture extending into the drum, and

whose edges constitute weirs for the over flow of the floatable concentrates; substan tially as described.

11, Apparatus for-the separation of loitable minerals from material with which they v are associated, said apparatus comprising a cry of the drum on the risingsidethexe'df, and a collector comprising a trough-structure extending into the drum, and whose edges eonstitut \veirs for the overflow of the floatable concentrates, the weir edges of the troughs being provided with adjustable wear-plates; substantially as described.

In testimony whereof I affix my signature. in presence of two witnesses.

'ARCHlBALI) Rt IJVINGSTON. \Vi tnesses M. A. BILL,

Joun CHEMIE. 

